Roncallo's Facebook posts indicate that he has been the dog's owner for at least four years.

The video was shot around 3 p.m. on April 20 on the downtown 4 train, according to TahSyi Kyng, who posted the clip to Instagram.

It shows the dog holding a 22-year-old woman's shoe in its mouth as subway riders yell at Roncallo to get the dog to release her. The dog eventually pulls the shoe off the woman's foot and Roncallo throws it back at her.

Kyng said the altercation started when Roncallo put the dog up on the subway seats and instructed it to lie down. As the animal did so, it bumped the woman, who told Roncallo to put the dog back on the floor. When he refused, the woman attempted to push the animal off the seat, despite Roncallo warning her not to touch his dog.

When she again pushed the dog, witnesses said, they both began to physically fight each other. That's when the dog seized the woman's foot as other passengers attempted to break up the fight.

The woman was able to walk away from the scene and did not appear seriously injured.

In a video of the arrest Thursday afternoon posted to Twitter by ABC7NY reporter CeFaan Kim, Roncallo repeatedly said, "She attacked me first," when asked about his actions and those of his dog.

After confirming that the dog was a service animal, an NYPD spokesperson told BuzzFeed News that Vinci has not been removed from Roncallo's care.

Facebook

Service animals are exempt from Metropolitan Transportation Authority rules, which state that "no person may bring any animal on or into any conveyance or facility unless enclosed in a container and carried in a manner which would not annoy other passengers."

Service animals must be harnessed and leashed — in the viral video, it is clear that Vinci is on a leash.